1. Field of the Invention
The present invention relates to a micro reforming reactor and a method of manufacturing the same. More particularly, the present invention relates to a micro reforming reactor for a fuel cell including a micro tunnel with a catalyst layer on the micro tunnel, and a method of manufacturing the same.
2. Description of the Related Art
A fuel cell is a power generation system for producing electrical energy through an electrochemical redox reaction of an oxidant and a fuel such as hydrogen, or a hydrocarbon-based material, such as methanol, ethanol, natural gas, or the like.
A fuel cell is a clean energy source that can replace fossil fuel energy sources. It includes a stack comprising a plurality of unit cells and produces various ranges of power output. Since a fuel cell has four to ten times higher energy density than a small lithium battery, it may be used as a small portable power source.
Exemplary fuel cells include polymer electrolyte membrane fuel cells (PEMFCs) and direct oxidation fuel cells (DOFCs).
A PEMFC has power characteristics that are superior to those of conventional fuel cells, as it has a lower operating temperature and faster start and response characteristics. PEMFCs can be applied to a wide range of applications such as for portable electrical power sources for automobiles, distributed power sources for houses and public buildings, and small electrical power sources for electronic devices.
A typical PEMFC system includes a plurality of unit cells arranged in a stack, a fuel tank for storing a fuel, a fuel pump for pumping fuel from the fuel tank to a reformer, and a reformer for reforming the fuel to produce hydrogen gas to be supplied to the stack. The stack generates electrical energy through an electrochemical reaction of the hydrogen gases and oxygen.
In such a fuel cell system, the stack that generates electricity typically includes a plurality of unit cells stacked adjacent to one another, where each unit cell includes a membrane-electrode assembly (MEA) and a separator (also referred to as a bipolar plate). The membrane-electrode assembly includes an anode (also referred to as a “fuel electrode” or an “oxidation electrode”) and a cathode (also referred to as an “air electrode” or a “reduction electrode”) separated from one another by a polymer electrolyte membrane. The separators work as passageways for supplying the fuel and the oxidant to the fuel cell, and also work as conductors for serially connecting the anode and the cathode in the membrane-electrode assembly.
Using the separators, hydrogen gas is supplied to the anode and oxygen is supplied to the cathode. An electrochemical oxidation reaction of the fuel occurs at the anode, and an electrochemical reduction reaction of oxygen occurs at the cathode. Due to movement of the electrons generated by the reactions, electricity, heat, and water are produced.